Inserted and applied medical devices are indispensable in modern-day medical practice. Inserted medical devices can include implantable ports, intravascular catheters, percutaneous tubing such as nephrostomy tubes, gastrostomy tubes, or colostomy tubes and the like, indwelling catheters, epidural catheters and external fixator pins. Inserted medical devices can put patients at risk for serious complications due to local and systemic infections, thrombosis and thrombophlebitis. They also can cause pain and discomfort due to inward pressure or compression or snagging of an exit site catheter tail. Applied medical devices such as electrodes that can be used to monitor heart conditions, brain activity or fetal movement, likewise can cause discomfort and are at risk for compression, snagging and inadvertent removal.
Inserted medical devices such as intravascular catheters can be used to administer long-term or repeated treatments such as chemotherapy, blood transfusions or blood draws, administration of high-calorie liquids and antibiotics while avoiding the need to start an IV each time. Although such devices provide convenient access, their use often negatively impacts patient well-being. Exemplary intravascular catheters include central vascular catheters, peripheral vascular catheters, midline catheters, peripherally inserted central catheters, hemodialysis catheters, pulmonary catheters, umbilical catheters and scalp vein catheters.
Another inserted medical device is an implantable port. An implantable port sits under the skin and connects to a catheter cannulating a large blood vessel. The port can be felt as a small bump underneath the skin and specialized needles, such as a Huber needle, can be used to access the port to administer treatments directly into the bloodstream. For short term treatments, the needle is withdrawn from the port. For longer treatments, the needle can be left in place connected to the port.
Regardless of the type of applied or inserted medical device in use, each requires some means of securement to the patient. Film dressing is well known for the purpose of covering medical devices and external attachments. Transparent, semi-permeable polyurethane dressings have become a popular means of dressing insertion sites (see, for example, U.S. Pat. Nos. 4,614,183 and 3,645,835). Transparent dressings help to secure devices, allow for continuous visual inspection of the device, permit patients to bathe and shower without saturating the dressing, and provide some limited protection against infection. However, there is a need for dressings that can prevent compression, constriction and pain associated with the inadvertent manipulation of the medical devices while also providing adequate protection from infection, snagging and dislodgement.
Improvements in dressings for wounds due to burns, chronic ulcers, donor sites, post-operative wounds, and a variety of other injuries are likewise needed. Trends in modern medical practice have shown that healing of wounds may be significantly improved by clinical intervention using methods and materials that optimize wound conditions to support the physiological processes of the progressive stages of wound healing. Wound dressings are generally classified as passive, interactive or bioactive products. Traditional wound dressings like gauze and tulle dressings are examples of passive products. These dressings are helpful in collecting heavy exudate drainage, but they require frequent changing, cause irritation and have a tendency to stick to the wound during body movement and dressing removal. Interactive dressing products can include polymeric films, hydrocolloid dressings and hydrogels. These types of materials are mostly transparent, permeable to water vapor and oxygen and impermeable to bacteria. These films are recommended for low exuding wounds in that they are typically overwhelmed by the accumulated exudate moisture during the heavy drainage phase of wound healing. Bioactive dressings deliver substances active in wound healing. Bioactive dressings can deliver therapeutic compounds or the dressing itself can be constructed from material having endogenous wound healing properties.
There is a need for improved dressings for the purposes of protecting inserted and applied medical devices, affixing external attachments as well as protecting wounds on patients with extensive burns, lacerations and skin damage.